(1) Field of the Invention
The present invention relates to a broadcasting apparatus and a broadcasting method that transmits contents data relating to a program as well as audiovisual data which makes up the program.
(2) Description of the Related Art
Conventionally, methods for transmitting contents data relating to a program as well as audiovisual data which makes up the program have been put to practical use. For instance, a broadcasting apparatus broadcasts a movie while transmitting information on the masterpieces of the actor who appears on the movie is transmitted as contents data, and a receiving apparatus presents the information in accordance with a user's selection. For another instance, a broadcasting apparatus broadcasts a commercial program, while information on the detailed explanations of the product in the commercial is transmitted as contents data and the receiving apparatus presents the explanations.
FIG. 1 shows a transmission schedule for the broadcasting data transmitted by the broadcasting apparatus. As shown in this figure, the broadcasting data consists of audiovisual data and contents data. Here, the contents data is repeatedly transmitted within the reproduction time period. For example, the contents data for CM1 is transmitted three times in the reproduction time period.
By repeatedly transmitting contents data in this way, a user can receive the contents data even when the user starts to watch the program from some midpoint of the program.
However, as shown in FIG. 1, the receiving apparatus has not received contents data at all at the start of the program, because the contents data is transmitted during the broadcasting time period for the program as well as the audiovisual data. Therefore, as shown in this figure, even if there is some image data that should be reproduced at the start of the program CM2, the receiving apparatus cannot present the image data for the period indicated by the diagonally shaded area in the figure (i.e., until the time t2). Furthermore, when a user wishes to select and reproduce an image data during broadcasting of a program and in case that the image data has not been received, the image data cannot be presented until the data has been received.